<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style type="text/css" media="screen">
		div::before{
			content: "楚乔";
			background-color: pink;
			border: 1px solid red;
			width: 100px;
			height: 100px;
			display: block;
			/* 类选择器 伪类选择器 就是选取对象
			伪元素选择器 本质上是插入一个元素(标签 盒子) */
		}
		div::after{
			content: "楚乔";
			background-color: pink;
			border: 1px solid red;
			width: 100px;
			height: 100px;
			display: block;
		}
	</style>
</head>
<body>
	<div>
		是
	</div>
</body>
</html>